Determine the percentage of calcium ion in Ca₃(PO₄)₂ . 

A)38.765%

B)12.92%

C).19.97%,

D)2.5797%

Answer:

A)38.765% 

Explanation:

First calculate the molecular mass of Ca₃(PO₄)₂ using the atomic mass of each element from the periodic table. Here, the molecular mass is equal to the sum of product of the atomic mass of each element and their corresponding subscript.

molecular mass = 3 x atomic mass of Ca + 2 x atomic mass of P + 8 x atomic mass of O

molecular mass = 3 x 40.08 amu + 2 x 30.97 amu + 8 x 16.00 amu

molecular mass = 310.18 amu

Then, calculate the total mass of the Ca²⁺ (calcium ion) component by multiplying its atomic mass and subscript as shown below.

total mass of Ca²⁺ = 3 x atomic mass of Ca

total mass of Ca²⁺ = 3 x 40.08 amu

total mass of Ca²⁺ = 120.24 amu

Finally, calculate the percentage calcium ion using the formula below.

percentage calcium ion = (total mass of Ca²⁺ / molecular mass) x 100% = (120.24 amu / 310.18 amu) x 100% = 38.765% (A)